Sealing arrangement

ABSTRACT

A rotary shaft is surrounded by a sleeve which is rotatable with it and which is in turn surrounded over all but an axial end portion by an inner annular housing. The axial end portion is provided with an external circumferential groove and the inner annular housing has in the region of this groove a radially directed outward flange which is connected with an outer annular housing surrounding the inner annular housing. A circlip is accommodated in a circumferential recess provided in the shaft adjacent an end of the sleeve and the circlip engages the sleeve to prevent its axial displacement with reference to the shaft. Temporary coupling devices are provided on the inner annular housing and can be moved into and out of the groove in the sleeve to thereby temporarily and releasably couple the inner annular housing with the sleeve.

0 I i United States Patent 1 1 1 1 3,743,302 Bach et al. 5] July 3, 1973SEALING ARRANGEMENT [75] Inventors: Meinhard Bach, 7 2 m g '7 fianceBobenheim-Roxheim; Friedrich Ass'stant gz fi 'g i Urban, Frankenthal,both of omey 1c ae n er Germany [73] Assignee: Klein Schanzlln & Beckerv [57] ABsTRACT Aktlengesellschaft, FrankenthaL- A rotary shaft issurrounded by a sleeve which is rotat- Germany able with it and which isin turn surrounded over all but an axial end portion by an inner annularhousing. The [22] 1971 axial end portion is provided with an externalcircum- [21 App] 213,47 ferentia] groove and the inner annular housinghas in the region of this groove a radially directed outward flangewhich is connected with an outer annular hous- [52] U.S. (ii 277/10,277/38, :277/65 g surrounding the inner annular housing A circlip is[51] Int. C F16] accommodated in a circumferential recess provided in 8Field of Search 277/9' the shaft adjacent an end of the sleeve and thecirclip 277/38 65 engages the sleeve to prevent its axial displacementwith reference to the shaft. Temporary coupling de- [56] References cuedvices are provided on the ,inner annular housing and UNITED STATESPATENTS can be moved into and out of the groove in'the sleeve 1,872,4988/1932 Rasmussen et al. 277/10 to thereby temporarily and releasablycouple the inner 1,896,795 2/1933 Kendall 277/11 annular housing withthe sleeve. 3,460,844 8/1969 Whittle 277/85 3,620,554 11 1971 'Ward etal. 277 11 9 Claims, 5 Drawing Figures .4 w T l l lll sat 2 9 3a 1 1 77a A I ,1 A9 FE /0 1' PATENIEDJUL n 5743.302

am 1 ur SEALING ARRANGEMENT BACKGROUND OF THE INVENTION The presentinvention relates generally to a sealing arrangement and moreparticularly to a mechanical sealing arrangement for use on a rotor.

Many rotors, which term includes rotatable shafts and analogous members,must be provided with suitable sealing arrangements, generally calledshaft-seals. A problem attendant in all known constructions of this typehas to do with the work required for installing the seals on the rotorthat is the shaft or the like, and the adjustment of the rotor,withreference to the seal, particularly in such apparatus as for instancerotary pumps. In all such instances, the adjustments and manipulationsrequired are relatively complicated which means that the installationand inspection times necessarily are long and that the installations andinspections are expensive. Furthermore, in these shaft seals whichutilize sliding ring seals there is usually inadequate protectionafforded against damage to these sliding ring seals which are highlysusceptible to such damage.

Additional disadvantages existing in the prior art include the fact thatafter repair or inspection, time consuming adjustments must frequentlybe carried out in order to obtain the same rotor position as before, soas to avoid a change in the hydraulic axial pressure. Furthermore duringrepair and inspection, the pump chamber itself if a pump is involvedmust be emptied or released of pressure, particularly in the case ofliquids having very steep saturation characteristics and in the case ofliquids or fluids which are poisonous or noxious, and also in the caseof liquids or fluids which are expensive. A particular disadvantage isconstituted by this last requirement in the case of pumps which pumpliquefied gases at minus temperatures, because the emptying of the pumpchamber or pressure release therefrom is very time consuming and are-liquefication of the gas is very.expensive.

SUMMARY OF THE INVENTION It is, accordingly, an object of the presentinvention to overcome the disadvantages of the prior art.

More particularly, it is an object of the present inven' tion to providean improved arrangement of the character here under discussion which isnot possessed of these disadvantages.

Another object of the invention is to provide such an improvedarrangement which is highly reliable in operation and can be manipulatedand adjusted rapidly and with little expense and experience.

In pursuance of these and other objects which will still become apparenthereafter, one feature of the invention resides in an arrangement of thecharacter here under discussion, which briefly stated comprises a rotorand sliding ring seal means including a sleeve surrounding a portion ofthe rotor rotatable therewith and having a main portion and an endportion which is provided with an external circumferential groove. Aninner annular housing surrounds the main portion and has an outwardlydirected radial flange in the region of the end portion, and an outerannular housing surrounds the inner annular housing and has an annularend face axially juxtaposed with the flange. Connecting means isprovided for releasably connecting the flange with the outer annularhousing, and retaining means is provided for retaining the sleeveagainst axial movement relative to the rotor and inner annular housing.In addition, there is provided temporary coupling means carried by theinner annular housing in the region of the flange thereof and movable toand from a position in which it extends into the groove of the sleevefor thereby temporarily coupling the inner annular housing with thesleeve against relative axial displacement.

By resorting to the present invention the actual sealing means itself iscapable of participating in an axial displacement of the rotor to theextent necessary for requisite adjustments of the arrangement. Thetorque is transmitted to the rotating components of the sliding ringsealing means by suitable connection with the rotor, for instance by aWoodruff key. The invention assures that only very short installationand inspection times are necessary and that all necessary installationsand inspections can be carried out in a very simple and highly efficientmanner. Furthermore, maximum protection can be afforded in this way tothe sliding ring seal components against damage while inspection orinstallation operations are carried out.

With the present invention it is assured that after an inspection therotor will assume precisely the same position with reference to theremainder of the arrange ment as it had before the inspection, withouthaving to carry out any measuring or adjustment operation, so that achange in the direction of the hydraulic forces acting upon the rotor orthe rotor system is precluded.

It is advantageous according to a further concept of the invention toprovide a stationary auxiliary sealing arrangement which is utilizedonly when the rotor is stationary, that is during repair, and inspectionor similar work, and which provides for sealing with respect to therotor during such operation, thereby obviating any necessity foremptying or de-pressurizing the pump chamber is the arrangement is usedin connection with a pump. This is particularly advantageous in the caseof pumps which act upon liquids at minus temperatures because of thetime consuming emptying or depressurizing and subsequentre-liquefication of a gas (if a gas was involved) are avoided. Theinvention has still an additional advantage in that a pre-assembledsealing unit can be maintained on hand in. case of urgent emergenciesand in the event that the already installed unit on the rotor shouldbecome defective. This of course greatly reduces the time involved.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary axial sectionthrough an arrangement according to the present invention, it beingunderstood that the rotor is shown in its entire width transverse to itsaxis of rotation but that only the righthand part of the annular sealingarrangement itself is illustrated, whereas the non-illustrated left-handpart is symmetrical relative thereto;

FIG. 2 is a view similar to FIG. 1, angularly displaced to the leftthrough and illustrating one adjustment stage in the adjustment of therotor with reference to the sealing unit;

FIG. 3 is a view similar to FIG. 2 illustrating another adjustmentstage;

FIG. 4 is a view similar to FIG. 3 illustrating the final adjustedoperating position of the arrangement shown in FIGS. 1 3; and

FIG. is a somewhat diagrammatic end-elevational view of FIG. 4, lookingtowards the right in that Figure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS For purposes of explanation butnot in any sense in a limiting manner it will be assumed herein that therotor R in FIGS. 1 5 is a rotary shaft having a vertical orientation asin FIG. 1, and is for instance a part of a rotary pump. The angulardisplacement through 90 towards the left in FIGS. 2 4 with respect tothe illustration in FIG. 1 has been chosen for space-saving reasons,although it should be understood that the rotor could of course beoriented horizontally or at an angle of inclination to the horizontalother than normal.

Discussing the drawing now in detail and firstly FIG. 1 thereof, it willbe seen that the sealing unit itself is temporarily coupled with therotor R by means of two eccenter arresting devices 2 mounted on theupper removable cover 1 of a sealing housing or inner housing 7 which issurrounded by an outer housing 8, and on which cover 1 the devices 2 aremounted for pivoting movement about the pivots 2a (see FIG. 5) to andfrom a position (the broken-line position of FIG. 5) in which theyextend in part into a circumferential groove 3a provided in the outercircumference of an end portion of a sleeve 3 which surrounds a part ofthe rotor R (see FIG. 1) and is fixedly connected therewith so that itwill rotate with the rotor R for instance by means of thediagrammatically illustrated Woodruff key 6.

The sleeve 3, which constitutes a part of the sliding ring seal means,is prevented from axial movement with reference to the rotor R by acirclip 4 which is lodged in a groove provided in the periphery of therotor R, (See FIG. 1) as well as by a shoulder 5 of the rotor R whichcooperates with a similar shoulder of the sleeve 3.

The rotating sliding ring seal components 18 are mounted on the sleeve 3and rotate with the same, and they as well as the stationary slidingring seal components 19 are accommodated in the inner housing 7. Thecomponents 19 are mounted or retained by covers 20 and 21 provided atopposite axial ends of the inner housing 7. A flange 7a of the innerhousing 7 extends radially outwardly and overlies an axially juxtaposedannular end face of the outer housing 8 with which it indirectly abutsand to which it is connected. Adjustment of the rotor system R iseffected via the flange 7 when the devices 2 are in their respective(broken-line) position shown in FIGS. 1 and 5.

After a single initial adjustment which is carried out with severaladjusting screws 9 as will be discussed later, the rotor system R issupported on the axial end face of the outer housing 8 via a two-partspacing ring 10 interposed between this axial end face and the flange 7aand having an axial length X (see FIG. 1) corresponding to the adjustedposition which it is desired to obtain. Screws 11 then connect theflange 7a with the housing 8.

FIG. 1 shows particularly clearly that between the housing 7 and thehousing 8 there are defined relatively wide (in axial direction of therotor R) annular spaces 12 with which channels 22 and '30 of housing 8and channels 23 and 29 of inner housing 7 communicate. A ring member 25is located in the interior of the inner annular housing 7 being providedwith a plurality of equi-angularly circumferentially distributed boresor apertures 250 as particularly clearly shown in FIG. 1. Thearrangement herein disclosed utilizes a blocking liquid which iscirculated through the sealing unit for lubrication and for coolingpurposes; this liquid is introduced via the inlet 24 from a suitablesource and fills from their via channels 22 and 23 into the ring 25whose apertures 25a distributed evenly about the circumference of thering 25 so that it can enter into the sealing compartment 28. A dammingbaffle 26 retards or dams the flow of the liquid which is then caused toflow out via the channels 29 and 30 and the outlet 27,to be returned tothe liquid reservoir from where the nonillustrated source receives itfor introduction into the inlet 24. Leakage fluid will collect in thespace 31 and can be controlled or removed via the connection 32 whichcommunicates with the space 31.

An auxiliary stationary seal 13 is provided which is to be utilized onlyif the sliding ring seal must be removed, for instance for repair orinspection. It must be understood that in FIG. l, fluid for instanceunder pressure will be pressed downwardly below the lower end of theouter housing 8 which could escape between the rotor R and the lower endwall of the housing 8 into the interior of the latter and into theinterior of the inner housing 7, and from there to the ambient regionsif the sliding ring seal has been removed. To avoid this, the stationaryauxiliary seal 13 is provided which, in the illustrated embodiment is inthe form of a hollow annular member 13a of elastically distendablematerial, for instance natural or synthetic rubber or synthetic plasticmaterial. The interior of this member 13a may be reinforced by anannular insert 13b of metal or suitable material, provided with passagescomnunicating with the inlet 33 which is adapted to be connected to asource of pressurized fluid. When such pressurized fluid is admitted viathe inlet 33 the member 13a will be radially inwardly distended intosealing engagement with the rotor R so that leakage into the housings 7and 8 is precluded by the auxiliary seal 13 and the sliding ring sealcan be removed from the housing 7 for inspection and- /or repair if andwhen desired. This eliminates any necessity for removing fluid contentsof the pump (assuming that the arrangement is utilized on a pump) or fordepressurizing the contents, thereby in turn reducing the inspection andrepair time and eliminating incidental expenses involved, for instancein re-liquefying gas which was originally present in liquid condition.

The installation of the unit on the rotor R assumed here to have avertical orientation as in FIG. I, will now be discussed with respect toFIGS. 2 5. It will be seen in FIG. 2 that the inner housing 7 with thesliding ring seal is first introduced into the outer housing 8 along therotor R when the latter is in its lowest end position as indicated bythe arrow in FIG. 2. The housing 7 is then inserted into housing 8 untilsleeve 3 rests on shoulder 5. During this movement the devices arepivoted about pivots 2a from the full-line to the brokenline position ofFIG. 5, so as to enter partially into groove 2a as shown in FIG. 2. Thiscouples sleeve 3 and housing 7 for joint movement. On sealing of sleeve3 upon shoulder 5, a circlip 4 is inserted as shown in FIGS. 1 and 2.

At this time, the amount of play Y between flange 7c and the juxtaposedend face of housing 8 (FIG. 2) is measured and a note made of it.

Sleeve 3 and rotor R are then shifted by means of screws 9 which bearwith their free ends on the endface of housing 8. When the rotor R hasreached its highest position, the play between flange 7a and thejuxtaposed axial end face of the housing 8 will be the distance Z asshown in FIG 3. This play is also measured and a note made thereof.

Of these two dimensions Y and Z the final desired operational positionof the rotor R is now determined, that is the play X of FIG. 1 iscalculated from them whereupon the ring 10 is provided which either hasan axial length corresponding to the dimension X or is shortened from alonger configuration until it has this axial length. The ring 10, whichmay be of two parts or which may be after its length-adjustment severedinto two parts, is not interposed between the axial end face of housing8 and the flange 7a whereupon the housing 7 is lowered by turning thescrews 9 in an opposite sense to that required previously, until theflange 7a rests on the ring 10. In this position there is no load on thescrews 9 and screws or bolts 11 are now utilized for conneting theflange 7a with the housing 8 in fixed relationship therewith. At thistime the frictional ehgagement of the portions of the devices 2 receivedin the groove 3a is usually too tight to permit the devices 2 to bepivoted to their inoperative full-line position of FIG. 5. Therefore,the rotor R is now shifted towards the left again in FIG. 4 (that israised if itis vertically oriented by about 2-3 tenths of a millimeterso that the friction is reduced and the devices 2 can now be pivotedfrom their broken-line position to their full-line position in FIG. 5 inwhich position they are withdrawn from the groove 3a as shown in FIG. 4.The operative position which the devices 2 assume in FIGS. 1 3 isdesignated in FIG. 5 with reference numeral 15 and the inoperativeposition is designated with reference numeral 14.

It will be appreciated that after inspection of the sliding ring sealcomponents, the proper positioning of the rotor R with respect to thesealing unit can be carried out without any necessity for takingmeasurements or making adjustments, as is clear from FIG. 1. It ismerely necessary to replace the inner housing 7 into the housing 8 andthen to replace the circlip 4 whereupon the flange 7a is raised by meansof the screws 9 to such an extent that the previously used ring 10 canbe inserted between the flange 7a and the end face of the housing 8. Thescrews 9 are then manipulated until the flange 70 again rests on thering 10 and can be secured to the housing 8 by means of the screws orbolts 11.

This, it will be seen provides for a construction and an operation whichavoid the disadvantages of the prior art and achieve all the objectswhich have been outlined above.

It will be understoodthat each of the elements described above, or twoor more together, may also find a useful application in other types ofconstructions differing from the types described above.

While the invention has been illustrated and described as embodied in amechanical shaft seal arrangement, it is not intended to be limited tothe details shown since various modifications and structural changes maybe made without departing in any way from the spirit of the presentinvention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledgereadily adapt it for various applications without omitting features thatfrom the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this invention andtherefore, such adaptations should and are intended to be cmprehendedwithin the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims.

We claim:

1. An arrangement of the character described, comprising a rotor;sliding ring seal means including a sleeve surrounding a portion of saidrotor rotatable therewith and having a main portion and an end portionwhich is provided with an external circumferential groove; an innerannular housing surrounding said main portion and having an outwardlydirected radial flange in the region of said end portion; an outerannular housing surrounding said inner annular housing and having anannular end face axially juxtaposed with said flange; connecting meansfor releasably connecting said flange withsaid outer annular housing;retaining means for retaining said sleeve against axial movementrelative to said rotor and said inner annular housing; and temporarycoupling means carried by said inner annular. housing in the region ofsaid flange thereof and movable to and from a position in which itextends into said groove for thereby temporarily coupling said innerannular housing with said sleeve against relative axial displacement.

2. An arrangement as defined in claim 1, said retaining means includinga circlip lodged in a circumferential groove provided in said rotoradjacent an axial end of said sleeve, said circlip being adapted forengagement with said axial end.

3. An arrangement as defined in claim 1, said temporary coupling meanscomprising at least one arm pivotally mounted on an end face of saidinner annular housing for movement to and from said position.

4. An arrangement as defined in claim 3, said arm being an eccenter arm.

5. An arrangement as defined in claim 3, said inner annular openinghousing having one end provided with an axially directed opening at saidend portion and including a removable cover for closing said opening,said arm being mounted on said cover.

6. An arrangement as defined in claim 5, said outer annular housinghaving a transverse end wall axially spaced from said one end and in theregion of the other end of said inner annular housing; and furthercomprising stationary sealing means in the region of said transverse endwall and operative for sealing the interior of said housing withreference to the ambient atmosphere at least at times.

7. An arrangement as defined in claim 6, said station ary sealing meanscomprising a hollow annular member of elastically distendable materialsurrounding a portion of said rotor with clearance, and distending meanscommunicating with the interior of said hollow annular member fordistending the latter into sealing engagement with said portion of saidrotor.

8. An arrangement as defined in claim 7, saud trans verse end wallhaving an aperture through which said rotor extends and which is boundedby a radially inwardly directed face provided with an inner circumfer- 78 ential groove, said hollow annular member being pressurized fluid.seated in said inner circumferential groove; and 9. An arrangement asdefined in claim 6', said stationwherein said distending means comprisesa passage ary sealing means comprising a pair of cooperatingcommunicating with the interior of said hollow annular sealing rings.member and adapted to communicate with a source of

1. An arrangement of the character described, comprising a rotor;sliding ring seal means including a sleeve surrounding a portion of saidrotor rotatable therewith and having a main portion and an end portionwhich is provided with an external circumferential groove; an innerannular housing surrounding said main portion and having an outwardlydirected radial flange in the region Of said end portion; an outerannular housing surrounding said inner annular housing and having anannular end face axially juxtaposed with said flange; connecting meansfor releasably connecting said flange with said outer annular housing;retaining means for retaining said sleeve against axial movementrelative to said rotor and said inner annular housing; and temporarycoupling means carried by said inner annular housing in the region ofsaid flange thereof and movable to and from a position in which itextends into said groove for thereby temporarily coupling said innerannular housing with said sleeve against relative axial displacement. 2.An arrangement as defined in claim 1, said retaining means including acirclip lodged in a circumferential groove provided in said rotoradjacent an axial end of said sleeve, said circlip being adapted forengagement with said axial end.
 3. An arrangement as defined in claim 1,said temporary coupling means comprising at least one arm pivotallymounted on an end face of said inner annular housing for movement to andfrom said position.
 4. An arrangement as defined in claim 3, said armbeing an eccenter arm.
 5. An arrangement as defined in claim 3, saidinner annular housing having one end provided with an axially directedopening at said end portion and including a removable cover for closingsaid opening, said arm being mounted on said cover.
 6. An arrangement asdefined in claim 5, said outer annular housing having a transverse endwall axially spaced from said one end and in the region of the other endof said inner annular housing; and further comprising stationary sealingmeans in the region of said transverse end wall and operative forsealing the interior of said housing with reference to the ambientatmosphere at least at times.
 7. An arrangement as defined in claim 6,said stationary sealing means comprising a hollow annular member ofelastically distendable material surrounding a portion of said rotorwith clearance, and distending means communicating with the interior ofsaid hollow annular member for distending the latter into sealingengagement with said portion of said rotor.
 8. An arrangement as definedin claim 7, saud transverse end wall having an aperture through whichsaid rotor extends and which is bounded by a radially inwardly directedface provided with an inner circumferential groove, said hollow annularmember being seated in said inner circumferential groove; and whereinsaid distending means comprises a passage communicating with theinterior of said hollow annular member and adapted to communicate with asource of pressurized fluid.
 9. An arrangement as defined in claim 6,said stationary sealing means comprising a pair of cooperating sealingrings.